反应详情

To a solution consisting of 3.2 g of 5-amino-6-fluoro-3-propargyl-2-benzothiazolone and 50 g of dioxane were dropwise added 2.4 g of trichloromethyl chlorocarbonate at a temperature in the range of from 5° to 15° C. and the resulting mixture was heated under reflux for six hours. A residue was obtained by distilling off the low-boiling material from the mixture under reduced pressure, and it was dissolved in 150 ml of dried toluene and filtered. From the resulting filtrate toluene was distilled off to obtain 3.6 g of 6-fluoro-5-isocyanato-3-propargyl-2-benzothiazolone having a melting point in the range from 134° to 135° C.

1. customof from 5° to 15° C.
2. temperaturethe resulting mixture was heated
3. temperatureunder reflux for six hours
4. customA residue was obtained
5. distillationby distilling off the low-boiling material from the mixture under reduced pressure, and it
6. dissolutionwas dissolved in 150 ml of dried toluene
7. filtrationfiltered
8. distillationFrom the resulting filtrate toluene was distilled off